DE102006006597B4 - Method and system for determining a steam temperature influencing sequence - Google Patents

Abstract

A method for determining a steam temperature influencing sequence for operating a plurality of soot blowers (110, 208, 210, 212, 214, 216, 218) in a steam power generator, the plurality of soot blowers (110, 208, 210, 212, 214, 216) , 218) can be used to spray a cleaning spray into a heat transfer area of the steam power generator used to generate electricity, the method comprising the following: operating a plurality of soot blowers (110, 112, 208, 210, 212, 214, 216, 218) in accordance with one Soot blowing sequence, wherein the soot blowing sequence dictates the flow rate of the cleaning spray used by each of the soot blowers (110, 112, 208, 210, 212, 214, 216, 218) over a time sequence; Measurement of the steam temperature in the heat transfer area during the time sequence; Calculation of several statistical parameters of the soot blowing sequence; and evaluating at least one of the plurality of statistical parameters according to a first criterion in order to determine whether the soot blowing-out sequence is the steam temperature influencing sequence.

Description

TECHNICAL APPLICATION

This patent relates generally to computer software, and more particularly to computer software for use in electrical power generation facilities.

BACKGROUND OF THE INVENTION

Power plants use different types of power generators for power generation, which can be subdivided into heat, nuclear, wind, hydropower and other power generators depending on the energy used to produce electricity. Each one of these different types of power producers operates under different restrictive conditions. For example, the output power of a heat energy generator is a function of the heat generated in a boiler, the amount of heat being determined by the amount of fuel that can be burned per hour, etc. Moreover, the output of the heat energy generator may also depend on the heat transfer efficiency depend on the boiler used in the combustion of the fuel. Similar restrictions also exist with other types of power plants. Moreover, in most boilers, the desired steam temperature setpoints at the final superheater and reheater outputs are constant, requiring that the steam temperature be kept within a narrow range around the setpoint values at all load levels.

Fuel-powered generators produce steam from water through combustion of fuel that flows through a series of pipes in the boiler. The steam is used to generate electricity by means of one or more turbines. However, combustion of certain types of fuels such as coal, oil, waste, etc. creates a significant amount of soot, slag, ash and other deposits ("soot") on various surfaces in the boilers, including the inner walls of the boiler and the outer walls of the pipes. in which the water flows through the boiler. The soot deposits in the boiler have various adverse effects on the degree of heat transfer from the boiler to the water and thus on the efficiency of the generator, which are operated via the boiler. For this reason, the soot problem in fuel-fired power plants that use coal, oil and other soot-producing fuels requires a solution. In view of the fact that not all fuel-fired power plants produce soot, in the following text of this patent the term "fuel-fired power plants" is used only for those power plants where soot is produced.

To solve the problems due to the formation and presence of soot in boilers of fuel-fired power plants, various methods are used. For example, in equipment operated by fuel-fired power plants, so-called soot blower components or equipment are used to remove soot. In fuel-operated power plants, various types of soot blowers are used, with which cleaning materials are injected through nozzles. These nozzles are located on the gas side of the boiler walls and / or on other heat exchanger surfaces. Such Rußausblaser use a variety of media such as saturated steam, superheated steam, compressed air, water, etc., to remove the soot from the boiler.

However, the process of soot blowing has implications for many aspects of boiler operation. For example, the process of soot blowing affects the heat transfer efficiency, the steam temperature control, the NOx concentration within the boilers, etc. For example, soot blowing in a water wall area of a boiler increases the rate of heat absorption in that water wall area, thereby increasing the temperature of the flue gas coming out of the water Oven area of the boiler escapes, increased. This means that the flue gases entering the convection zone may have a lower temperature, which may result in less heat absorption in an overheat area and a reheater area, and thus may also reduce the steam temperature in these areas. On the other hand, the process of soot blowing in the convection area of a boiler increases the heat absorption rate and results in an increased steam temperature.

Various qualitative effects of Rußblasblasens are well known. However, it is difficult to determine the exact quantitative consequences of soot blowing on the efficiency and steam temperature of fuel-fired power plants. Compensation techniques used by existing control systems include the use of a PID controller which adjusts at least one of the following parameters to compensate for the effect of soot blowing: spray flow, burner tilt, and flue gas Redirect register. Often, however, such feedback compensation can only react responsively and cause significant steam temperature variations. It is therefore necessary to develop a systematic method of generating a feed-forward signal to compensate for the effects of soot blowing.

In today's power industry and the competitive environment there, where utilities use a number of complex control systems to control operating costs and increase the efficiency of power plants, it is important to understand the effects of soot blower operation, so that both operators as well as control systems can make informed decisions about how to compensate for the disturbances caused by soot blowdown. Thus, there is a need to provide better quantitative information about the effects of soot blowing so that any adverse or negative effects of soot blowing can be more effectively compensated.

document US 4,718,376 A. discloses a method for controlling a sootblowing operation in a power boiler or a chemical recovery boiler.

document US 5,181,482 A. discloses a method and system for controlling and guiding a sootblowing operation based on continuous monitoring of the factory and based on model calculations. The continuous monitoring is done by a factory-distributed control system (DCS) that communicates with a computer.

document US 6 325 025 B1 discloses a sootblower optimization system. The removal of combustion deposits from the surface of a fuel boiler is optimized by using a sootblower to direct a cleaning medium with adjustable operating parameters against a surface of the boiler to remove the accumulated deposits.

document US Pat. No. 6,758,168 B2 discloses a method and apparatus for sootblowing a regeneration vessel. The sootblowers of the regeneration boiler are divided into sootblower groups and a sootblower interval is determined for the sootblowers. For each sootblower group of the regenerator, a soiling index is determined and relative frequency values calculated.

BRIEF DESCRIPTION OF THE DRAWINGS

The present patent is illustrated in the accompanying drawings, which are exemplary and not limiting. Equal references in the drawings refer to similar elements.

1 is a block diagram of a power distribution system.

2 is a block diagram of a boiler in a fuel-fired power plant.

3 is a flowchart of one for the boiler in 2 used for the soot blow-out process.

4 FIG. 13 is a block diagram of a reheat (or overheat) region of the in 2 shown boiler.

5 is a diagram of the operation of in 4 represented Rußausblaser.

6 is a time curve of a feed-forward signal for the spray controls of the boiler in FIG 4 ,

7 is a flowchart for an evaluation program, which serves to determine whether a Rußausblasesequenz influence on the steam temperature or not.

DETAILED DESCRIPTION OF THE EXAMPLES

A system for analyzing the effect of soot blower operation in the heat transfer area of a power plant determines and calculates a steam temperature impact sequence Feedforward signal to be applied to a steam temperature control system for the heat transfer area. The system operates a group of soot blowers several times and collects quantitative data relating to the steam temperature during and after each individual soot blow-out cycle. A computer program used by the system analyzes the quantitative data, generates a series of statistical parameters to evaluate the effect of soot blower operation on steam temperature according to a given sequence, and determines if the given sequence has an effect on the steam temperature. Accordingly, the system determines a feed forward signal based on the steam temperature biasing sequence and directs the feedforward signal to a steam temperature control system used by the heat transfer area to compensate for any adverse effects of soot blowdown. The following figures describe a realization of this system in a coal or oil fired power plant.

1 shows a power distribution system 10 including a high voltage network (HS network) 12 that with a consumer network 14 and one or more RU networks 16 . 18 can be connected. The RU network 16 is with a second HS network 20 connected, and the RU network 18 consists of one or more power plants 22 - 26 which can be implemented as any type of power plant such as nuclear power plants, hydroelectric power plants, thermal power plants, etc. In addition, each of the power plants 22 - 26 include any number of individual power generators.

The operation of the power supply network 18 and the power plants 22 - 26 can be highly complex. For the smooth operation of the power supply network 18 It is therefore necessary for each of the power plants 22 - 26 with very high precision and in a highly predictable way. To ensure that each of the power plants 22 - 26 Power plants can deliver the power they need to deliver with the greatest possible efficiency 22 - 26 different control systems to ensure the efficient operation of each section of each of the power plants 22 - 26 to ensure.

For example, fuel-fired power plants that use coal, oil, gas, or other fuels for power generation use control systems to ensure the quality and quantity of fuel delivered to the furnace to ensure optimum properties of the steam flowing through the individual boilers, etc. Fuel-fired power plants typically have one or more boilers in which superheated steam is generated by passing water through a series of pipes in the boiler. The superheated steam then enters a steam turbine where it drives the turbine and a power generator connected to the turbine to produce electricity.

As already mentioned, soot, ash and other deposits on the walls of the water-carrying pipes cause a reduction in the heat which is transferred by the combustion of the fuel to the water and the steam flowing through the pipes. In order to ensure maximum heat transfer to the water and the steam flowing through the boiler tubes, soot blowers are used in the boiler, walls and pipes, which regularly blow off the soot accumulated on the pipes.

2 shows a cross section through a typical boiler 100 and the associated Rußausblasersystem. The kettle 100 is used to generate saturated steam (or superheated steam for once-through boilers) in the furnace area 102 as well as superheated steam in a convection area 104 , The convection area 104 may include overheating and reheating. The kettle 100 contains several overheating and reheating pipes 106 in the convection area 104 are arranged, these pipes 106 to transport water and superheated steam. The kettle 100 has, as shown in the figure, several stationary Rußblblaser 110 as well as several non-stationary soot blowers 112 ,

As discussed earlier, the process of soot blowing can affect many aspects of boiler operation. To the efficient operation of the boiler 100 It is therefore necessary to analyze the effects of the soot blowing process. 3 is a flowchart of a program 150 for the analysis of the effects of soot blowing on the operation of the boiler 100 by measuring its effects on the temperature of the superheated steam and / or the reheat steam. This analysis program 150 can be realized as software, firmware, hardware or any combination thereof.

Specifically, the analysis program operates 150 the soot blowers of a given area of the boiler 100 several times, each actuation of the soot blower following a predetermined pattern. During each of these operations, the analysis program is detected 150 Data related to diverse Characteristics of the spray flow used by the soot blowers in the given range, such as spray flow, etc., as well as its influence on the steam temperature of the given range. After collecting the data, the analysis program evaluates 150 one or more statistical quantities of acquired data to determine a steam temperature impact sequence. By means of this steam temperature influencing sequence determines the analysis program 150 then a feed forward signal for use by one from the boiler 100 used temperature control system.

Considering the detailed function of the analysis program 150 operates a program block 152 the soot blower 110 and 112 based on a series of predefined soot blow-off sequences. Since some of the boilers may already be in operation in accordance with previously defined soot blow-out methods, it may be necessary to modify these methods. Alternatively, the program block 152 select one or more carbon black blowing sequences currently used by the boiler and acquire the data associated with those sequences. The program block 152 can capture data using sequences that span one or more areas of the boiler 100 or for one or more types of carbon black blowing out 110 - 112 are specific, etc. So the program block 152 For example, other sequences for the collection of data in connection with the Rußausblasern in the furnace area 102 use as for the collection of data in connection with the Rußausblasern in the convection area 104 , Alternatively, the program block 152 Capture data using different sequences for stationary soot blowers and non-stationary soot blowers.

Each of the analysis program 150 used different sequences, regardless of whether they are for a specific area of the boiler 100 or for a particular type of soot blower, the operation of a number of Rußausblaser in a defined manner. 4 shows an example of realization of the application of soot blower sequences in the reheat area of the convection area 104 ,

4 is a schematic representation of the reheat area 200 with a heat exchanger 202 in the flow path of the flue gas from the boiler 100 , The reheat area 200 can be part of a convection area 104 out 2 be. The heat exchanger 202 includes a number of pipes 204 for transporting steam in a mixer 206 is mixed with water spray. The heat exchanger 202 converts the water-steam mixture into superheated steam. The in the reheat area 200 flowing flue gases are indicated schematically by the arrows 209 that the reheat area 200 leaving flue gases schematically by the arrows 211 shown. The reheat area 200 includes in the figure six soot blower 208 . 210 . 212 . 214 . 216 and 218 which blow out a spray mixture to remove soot from the outside surface of the heat exchanger 202 to remove. The soot blower 208 - 218 can be operated according to a defined Rußausblasesequenz, which specifies the order in which each of the Rußausblaser 208 - 218 is turn on. Once the soot blower 208 - 218 work according to this defined sequence, the program block detected 152 Data on the temperature of the steam in the reheat zone 200 ,

The program block 152 collects data in connection with the operation of the soot blower 208 - 218 and its effects on various characteristics of the steam by the soot blower 208 - 218 turns on for an operating period and then the Rußausblaser 208 - 218 for a rest period. This will be in 5 through the bend 250 further clarifies where the Rußausblaser 208 - 218 during the operating period 252 be operated according to a predetermined Rußausblasesequenz and during the rest period 254 are turned off.

The program block 152 generally collects data during the soot blow-out period 252 and at the beginning of the rest period 254 represent the effect of the Rußausblasevorgangs. The number of cycles during which each of the various predetermined sequences must be executed before the acquired data can be analyzed can be determined by the boiler operator 100 be determined. However, as a rule, the previously defined sequences must be performed approximately thirty times in order to obtain statistically significant information about the effects of the soot blowdown sequences on the steam temperature.

Following this, a program block calculates 154 from the program block 152 collected data various statistical parameters. To determine if an i. Sequence resulting from the operation of the soot blower 208 - 218 if the steam temperature is affected or not, the program block calculates 154 various statistical parameters that are related to those for the i. Refer to sequence acquired data. It is assumed that the i. Sequence is executed multiple times, with the duration of each execution cycle defined as soot blowing influence time (SITi) and each cycle characterized by an index j (j = 1 to N). If the i. Sequence actually affects the steam temperature or not, is determined on the basis of the evaluation of various statistical parameters, which are defined below by the equations (1) to (7): STV _{pos, j} = T _{max, i, j} - T _{0, i, j} (1) STV _{neg, i, j} = _{Tmin, i, j} - T0 _{, i, j} (2)

STV _{pos, i, j} is the positive steam temperature variance when the i. Sequence to the j. Time is executed. STV _{neg, i, j} is the negative steam temperature variance when the j. Sequence to the j. Time is executed. T _{0, i, j} is the initial steam temperature when the i. Sequence to the j. Time starts. T _{max, i, j} is the maximum steam temperature when the i. Sequence to the j. Times, and T _{min, i, j} is the minimum steam temperature when the i. Sequence to the j. Time is executed.

STV _{avg, i, j} is the mean steam temperature when the i. Sequence to the j. Time for the duration SIT _{i is} executed. M is the number of detection points during the period SIT _i . T _{k, i, j} is the steam temperature reading when the i. Sequence to the j. Is executed at the time of detection k. SFV _{pos, i, j} = F _{max, i, j} - F _{0, i, j} (4) SFV _{neg, i, j} = F _{min, i, j} - F _{0, i, j} (5)

SFV _{pos, i, j} is the positive spray flow variance when the i. Sequence to the j. Time is executed. SFV _{neg, i, j} is the negative spray flow variance when the i. Sequence to the j. Time is executed. F _{0, i, j} is the initial spray flow when the i. Sequence to the j. Time is executed. F _{max, i, j} is the maximum spray flow when the i. Sequence to the j. Time is executed. F _{min, i, j} is the minimum spray flow when the i. Sequence to the j. Time is executed.

SF _{avg, i, j} is the average spray flow when the i. Sequence to the j. Times for the duration SIT _{i is} running. M is the number of detection points during the period SIT _i . F _{k, i, j} is the spray flow measurement when the i. Sequence to the j. Is executed at the time of detection k. SFO _{i, j} = F _{e, i, j} - F _{0, i, j} (7)

SFO _{i, j} is the spray flow shift. F _{e, i, j} is the spray flow after a waiting time after i. Sequence to the j. Times. F _{0, i, j} has already been defined before.

Then calculates the program block 154 using the values obtained by equations (1) to (7) for various statistical parameters, various averages and standard deviations for the i. Sequence. The equations for these averages are set forth in Table I below. Table I

The standard deviations are calculated by means of the equations listed in Table II below. Table II

Once the program block 154 the various mean values and the various variance values for the i. Sequence has calculated determines a program block 156 whether the i. Sequence affects the steam temperature or not. The operation of the program block 156 becomes more detailed in 7 shown. If it is determined that the i. Sequence does not affect the steam temperature, the program block gives the control to the program block 152 back, and the analysis program 150 begins with the analysis of another sequence.

If it is determined that the i. Sequence affects the steam temperature, calculates a program block 158 a feedforward signal coming in from the boiler 100 used steam temperature control system is transmitted. In an implementation of the analysis program 150 the feedforward signal is sent from the boiler 100 transfer used spray valves. The mean total amount of spray flow to compensate for the effect of i. Sequence on the steam temperature is determined according to the following equation 8:

E _i is the mean total amount of spray change for one cycle of i. Sequence. F _{0, i, j} and F _{k, i, j} have already been defined above, and Δt is the length of the measurement interval.

Once the program block 158 determines the value of E _i determines a program block 160 the shape of the feedforward signal such that the total amount of spray caused by the advance control signal is equal to E _i . Therefore, when the feedforward signal is plotted against time, the absolute value of the area under the feedforward signal is equal to E _i . It will be apparent to those skilled in the art that the feedforward control signal may take on various forms - for example, triangle, exponential, etc. - where the absolute value of the area under the forward control signal is still equal to E _i .

The curve 260 in 6 is an example of a triangular feedforward signal, that of the curve 260 covered shaded area 262 is equal to E _i . The operator of the boiler can determine the position of point A on each point over the entire length of the curve 260 set as long as the absolute value of the area 262 under the curve is equal to E _i . In addition, the feed forward signal can also be added to any feedforward signal present from the control system of the boiler 100 already in use, with this existing feed forward signal from another program within the boiler 100 used control system can be calculated.

Whether the feedforward control signal is positive or negative is determined from the values of mean average spray flow variance μ _{SFV, avg, i} and average spray flow displacement μ _{SFO, i} . If both the value of the mean average spray flow variance μ _{SFV, avg, i} and the mean spray flow shift μ _{SFO, i are} negative, the feedforward control signal must be off 6 can also be negative. On the other hand, if both the value of the average average spray flow variance μ _{SFV, avg, i} and the mean spray flow displacement μ _{SFO, i are} positive, then the feed forward signal must be positive.

How out 3 can be seen, sends the program block 160 as soon as he has the shape and area of in a certain area of the boiler 100 to be used feed forward signal to the control system of the area concerned. The program block 160 may specify the feed-forward signal to the control system of the section in question for a longer period of time, such as about one month, and during this entire time to acquire steam temperature data in the relevant area of the boiler.

A program block 162 Determines, based on one or more predefined criteria, whether the goal of the realization of the analysis program has been achieved or not. One from the program block 162 criterion used to determine if the target is the analysis program 150 is reached or not, the question is whether (1) the distribution of the various from the analysis program 150 is still largely a normal distribution and (2) (a) whether μ _{STV, avg, i} <0, ie whether the absolute value of μ _{STV, neg, i is} significantly smaller than the previous absolute value of μ _{STV , neg, i} or (b) whether μ _{STV, avg, i} > 0, ie whether the absolute value of μ _{STV, pos, i is} significantly smaller than the previous value of μ _{STV, pos, i}

For the technically versed it can be seen that the program block 162 condition (2) (a) checks to determine that if the average of STV _{avg, i, j is} negative, the value of μ _{STV, neg, i is} less than before execution of the analysis program 150 which means that the size of the negative variance has decreased. On the other side, the program block checks 162 condition (2) (b) to determine that if the average of STV _{avg, i, j is} positive, the value of μ _{STV, pos, i is} less than before execution of the analysis program 150 which means that the magnitude of the positive variance has decreased.

If the program block 162 determines that the goal of the execution of the analysis program 150 is reached, uses the analysis program 150 the feedforward control signal continues in its current form when the current soot blowing sequence is executed next time. Otherwise, a program block changes 164 the feed-forward signal, which is then used in the modified form in the next execution of the current soot blowing sequence.

7 shows a program 280 for statistical evaluations, that of the program block 156 can be executed to determine if the i. Sequence actually affects the steam temperature or not. To determine if the i. Sequence influences the steam temperature or not, several different criteria can be used, each of which one or more of the various already developed above statistical parameters of i. Sequence evaluates. In addition, applying these criteria, the thresholds at which the statistical parameters are compared depend on the degree of confidence required to assess whether the i. Sequence affects the steam temperature or not. Therefore, not all of the diverse, in the evaluation program 280 used in each case for the determination of a steam temperature-influencing sequence.

First, evaluate a program block 282 the statistical distribution of each of the following statistical parameters: STV _{pos, i, j,} STV _{neg, i, j,} STV _{avg, i, j,} SFV _{pos, i, j,} SFV _{neg, i, j,} SFV _{avg, i, j} and SFO _{i, j} (for j = 1, 2, ..., N). In particular, the program block determines 282 whether these statistical parameters for the i. Sequence are approximately normally distributed or not. By means of the program block 282 can be a user of the evaluation program 280 determine what deviation from the normal distribution is allowed for these statistical parameters. In an alternative implementation, the program block 282 merely require that a weighted combination of all these parameters fall within a predetermined deviation range. In addition, other criteria may be used to assess whether the statistical parameters are normally distributed. In addition to the normal distribution check, the standard deviations of these normally distributed data must be within certain ranges that can be specified by the plant operator / engineer.

Afterwards, a program block judges 284 whether μ _{STV, pos, i} and μ _{STV, neg, i are} greater (less) than their predetermined limits, if μ _{STV, avg, i is} positive (negative). The predetermined limits (ie, the predetermined negative steam temperature variance and the predetermined positive steam temperature variance) may be determined by the user of the analysis program 150 such as a plant operator, an operator of the control system, etc. are specified.

A program block 286 judges whether μ _{SFV, pos, i} and μ _{SFV, neg, i are} larger (smaller) than their predetermined limits when μ _{STV, avg, i is} positive (negative). Again, the predetermined limits (ie, the predetermined negative steam temperature variance and the predetermined positive steam temperature variance) by the user of the analysis program 150 such as a plant operator, an operator of the control system, etc. are specified.

Afterwards, a program block judges 288 Whether or not the mean spray flow shift μ _{SFO, i is} outside of a first defined range, the first defined range being set by an operator of the boiler as an upper spray flow value and a lower spray flow value. This ultimately means that the program block 288 judges whether the mean spray flow shift μ _{SFO, i} (1) is higher than the predetermined upper spray flow value or (2) lower than the predetermined lower spray flow value. Finally determined on the basis of the evaluations in the program blocks 282 - 288 a program block 290 whether the i. Sequence actually affects the steam temperature or not.

Although the above text contains a detailed description of several different aspects of the invention, it should be understood that the scope of the invention is defined by the description of the claims at the end of this patent. The detailed description is to be understood only as an example and does not describe every possible embodiment of the invention, since a description of each possible expression would not be possible, if not completely impossible, with a realistic outlay. Numerous alternative forms could be realized using current technologies or technologies developed after the date of filing of this patent, which would still be covered by the claims describing the invention.

Thus, numerous modifications and variations of the techniques and structures described and illustrated herein may be made without departing from the spirit and scope of the present invention. Accordingly, it should be understood that the methods and apparatus described herein are illustrative only and not limiting in scope of the invention.

In one embodiment of the method according to the invention, it is provided that the heat transfer area consists of at least one of the following elements: (1) an overheat transfer area; (2) a reheat transfer area; and (3) a water wall area.

Claims (19)

Method for determining a steam temperature influencing sequence for operating a plurality of soot blowers ( 110 . 208 . 210 . 212 . 214 . 216 . 218 ) in a steam power generator, wherein the plurality of soot blower ( 110 . 208 . 210 . 212 . 214 . 216 . 218 ) are used to spray a cleaning spray into a heat transfer area of the steam power generator used for power generation, the method comprising: operating a plurality of soot blowers ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) according to a Rußausblasesequenz, wherein the Rußausblasesequenz dictates the flow of the cleaning spray that from each of the Rußblblaser ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) is used over a time sequence; Measuring the steam temperature in the heat transfer area during the time sequence; Calculation of several statistical parameters of the soot blowing sequence; and evaluating at least one of the plurality of statistical parameters according to a first criterion to determine if the soot blowing sequence is the steam temperature affecting sequence. The method of claim 1, wherein the first criterion includes: a mean positive steam temperature variance is greater than a defined positive steam temperature variance, and a mean negative steam temperature variance is greater than a defined negative steam temperature variance when a mean average steam temperature is positive; and the mean positive steam temperature variance is less than the defined positive steam temperature variance and the mean negative steam temperature variance is less than the defined negative steam temperature variance when the average average steam temperature is negative. The method of claim 1, wherein the first criterion includes at least one of the following elements: a) a positive steam temperature variance of the Rußausblasesequenz is distributed approximately normally; b) a negative steam temperature variance of the Rußausblasesequenz is distributed approximately normally; c) a mean steam temperature variance of the Rußausblasesequenz is distributed approximately normally; d) a positive spray flow variance of the soot blowing sequence is approximately normally distributed; e) a negative spray flow variance of the Rußausblasesequenz is distributed approximately normally; such as f) a Sprühdurchflussverschiebung the Rußausblasesequenz is distributed approximately normally. The method of claim 1, wherein the first criterion further includes: a mean spray flow variance and a mean negative spray flow variance are greater than the defined limits for the spray flow variance when a mean spray flow variance is positive; the mean spray flow variance and the mean negative spray flow variance are less than the defined limits for the spray flow variance when a mean spray flow variance is negative; a mean spray flow shift of the soot blowing sequence is greater than a defined upper spray flow value or less than a defined lower spray flow value. The method of claim 1, wherein the cleaning spray consists of at least one of the following components: 1. saturated vapor; 2. superheated steam; 3. compressed air; as well as 4th water. The method of claim 1, further comprising determining a feed forward signal whose absolute integer value is equal to a mean total amount of cleaning spray change for the steam temperature affecting sequence. The method of claim 6, wherein: the feedforward signal is negative when: 1. an average average spray flow variance for the steam temperature control sequence is less than zero; and 2. the mean spray flow shift for the steam temperature control sequence is less than zero; and the feed forward signal is positive when: 1. the average average spray flow variance for the steam temperature control sequence is greater than zero; and 2. the mean spray flow shift for the steam temperature control sequence is greater than zero. Method according to claim 7, further comprising the feed-forward signal to a boiler steam temperature control system ( 100 ) is sent. The method of claim 8, wherein the shape of the feedforward signal corresponds to at least one of the following forms: 1. linear; 2. polynomial; 3. exponential; and 4. hyperbolic. The method of claim 8, further comprising evaluating the results of applying the feedforward signal in accordance with the feed forward signal, the evaluation including: a) determining the magnitude of a negative steam temperature variance when a mean steam temperature is negative; and b) Determining the size of a positive steam temperature variance when a mean steam temperature is positive. System for determining a steam temperature influencing sequence for operating a plurality of soot blowers ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) in a steam power generator for generating electricity, wherein the plurality of soot blower ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) are used to spray a cleaning spray into a heat transfer area of the steam power generator used to generate the power, the system comprising: an actuation module configured to operate a plurality of soot blowers ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) according to a Rußausblasesequenz, wherein the Rußausblasesequenz dictates the flow of the cleaning spray that from each of the Rußblblaser ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) is used over a time sequence; Measuring module adapted for measuring the steam temperature of the heat transfer area during the time sequence; Calculation module adapted to calculate a plurality of statistical parameters of the soot blowing sequence; and evaluation module configured to evaluate at least one of the plurality of statistical parameters according to a first criterion to determine whether the soot blowdown sequence is the steam temperature influence sequence. The system of claim 11, wherein the first criterion includes: a mean positive steam temperature variance is greater than a defined positive steam temperature variance, and a mean negative steam temperature variance is greater than a defined negative steam temperature variance when a mean average steam temperature is positive; and the mean positive steam temperature variance is less than the defined positive steam temperature variance and the mean negative steam temperature variance is less than the defined negative steam temperature variance when the average average steam temperature is negative. The system of claim 11, wherein the first criterion includes at least one of the following elements: a) an approximately normally distributed positive steam temperature variance of the Rußausblasesequenz; b) an approximately normally distributed negative steam temperature variance of the Rußausblasesequenz; c) an approximately normally distributed average steam temperature variance of the Rußausblasesequenz; d) an approximately normally distributed positive spray flow variance of the soot blowing sequence; e) an approximately normally distributed negative spray flow variance of the Rußausblasesequenz; such as f) an approximately normally distributed Sprühdurchflussverschiebung the Rußausblasesequenz. The system of claim 13, wherein the first criterion further includes: a mean spray flow variance and a mean negative spray flow variance greater than the limits defined for the spray flow variance when a mean spray flow variance is positive; the mean spray flow variance and the mean negative spray flow variance are less than the limits defined for the spray flow variance when a mean spray flow variance is negative; a mean spray flow shift of the soot blowing sequence is greater than a defined upper spray flow value or less than a defined lower spray flow value. The system of claim 11, further comprising a feedforward signal configured to determine a feed forward signal whose absolute integer value is equal to a mean total amount of cleaning spray change for the steam temperature affecting sequence. The system of claim 15, wherein: the feedforward control signal is negative when: 1. a mean average spray flow variance for the steam temperature control sequence is less than zero; and 2. the mean spray flow shift for the steam temperature control sequence is less than zero; and the feed forward signal is positive when: 1. the average average spray flow variance for the steam temperature control sequence is greater than zero; and 2. the mean spray flow shift for the steam temperature control sequence is greater than zero. The system of claim 16, further comprising a control module configured to send the feedforward signal to spray valves within a steam temperature control system of the boiler. The system of claim 17, further comprising a feedback module arranged to adjust the results of the transmission of the feedforward signal to spray valves within the steam temperature control system of the boiler ( 10 ), the evaluation comprising: 1. determining the magnitude of a negative steam temperature variance when a mean steam temperature variance is negative; and 2. Determining the magnitude of a positive steam temperature variance when a mean steam temperature variance is positive. Device for determining a steam temperature influencing sequence for operating a plurality of soot blowers ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) in a steam power generator for generating electricity, wherein the plurality of soot blower ( 110 . 112 . 208 . 210 . 212 . 214 . 216 . 218 ) are used to spray a cleaning spray into a heat transfer area of the steam power generator used for power generation, the apparatus comprising: an interface; and a controller communicating with the interface configured to operate a plurality of soot blowers according to a soot blowing sequence, wherein the soot blowing sequence dictates the flow of the cleaning spray used by each one of the soot ejectors over a time sequence; it measures the steam temperature of the heat transfer area during the time sequence; it calculates several statistical parameters of the soot blowing sequence; and evaluating at least one of the plurality of statistical parameters according to a first criterion to determine if the soot blowdown sequence is the vapor temperature affecting sequence; that it determines a feedforward signal whose absolute integer value is equal to a mean total amount of cleaning spray change for the steam temperature affecting sequence; and sending the feedforward signal to spray valves within a boiler steam temperature control system.

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